The LHC Dumps Its Last Beam For Two Years: The particle accelerator is shutting down for repairs and upgrades th...

With the flip of a single red switch, the operators of the Large Hadron Collider cleared the last near-light-speed protons from the particle accelerator early this morning. Such "dumps," which divert the LHC's particle beams from their circulating ring and into two 10-ton graphite blocks , are routine. They can occur multiple times a day to protect the collider from beams that become unstable. But today's dump is expected to be the last one for two years , as physicists and engineers work to repair and upgrade the facility, with the aim of nearly doubling its power. The coming campaign, dubbed "Long Shutdown 1," will span all 27 kilometers of the LHC's accelerator ring. The chief aim will be to fix some 10 170 high-current connections between superconducting magnets. A single faulty connection between two magnets was responsible for the explosion in September 2008 that des...